Glanzmann thrombasthenia (GT) is an autosomal recessive platelet disorder caused by mutations in the ITGA2B or ITGB3 genes encoding the plasma membrane glycoproteins αIIb (GPIIb, CD41) and β3 (GPIIIa, CD61), respectively. Here, ITGB3 is linked to Glanzmann thrombasthenia 1.